A Phase I program is proposed to investigate the use of TRDC's passive air bag materials to construct a lightweight, low-cost "air helmet" for equestrians and bicyclists. A previous SBIR Phase I effort with AoA demonstrated that this novel passive air bag technology could be developed into thin, light cushioning materials that absorb significantly more impact energy than available foams. At velocities approximating a fall from a standing position, this new material absorbed 20% more energy than one of the best available shock-absorbing foams, with only half the foam's thickness and one fourth its weight. The proposed project would investigate the feasibility of modifying this passive air bag technology for use in helmets by testing the material's energy absorption ability at the much higher levels of impact experienced in bicycling and riding accidents. The program also will explore the material's potential to be manufactured at a lower cost than current polystyrene helmets. The project could provide a method of less expensive and lighter protection against head injuries to riders of bikes and horses; more compact helmets might also find greater acceptability to appearance-conscious young bicyclists, put at great risk now by their reluctance to wear any helmet at all.